PREVALENCE AND RISK FACTORS OF SENSORY-NEURAL HEARING LOSS AMONG TELEPHONE OPERATORS.

Abstract

Objectives: this study was carried out to evaluate the prevalence of sensory-neural hearing loss (SNHL) among telephone operators and its risk factors specially the effect of headset noise on the hearing ability of the telephone operators. Methods: a cross-sectional study was carried out on 58 telephone operators and 30 administration staff workers at Mansoura Telecommunications Company in Egypt. All participants were interviewed using a structured questionnaire including personal, medical and occupational history; and underwent an audiometric examination. Audiometric evaluation was done to evaluate hearing threshold levels (HTLs) for air and bone conduction for both right and left ears of all participants. Background noise was measured both at telephone operator and administration departments. Results: telephone operators had significantly higher prevalence of acoustic shock symptoms and decreased hearing sensitivity (46.6% and 37.9 %, respectively) compared to the controls (3.3% and 13.3%, respectively). Telephone operator had significantly higher HTLs compared to the controls, for air and bone conduction for both ears at lower and higher frequencies without the characteristic notch of noise induced hearing loss (NIHL). Among telephone operators, headset users had higher HTLs compared to headset non users, for air and bone conduction at the higher frequencies for both ears but more obviously in the left ear. There were 26 (44.8%) cases of SNHL among the telephone operators versus no cases among the controls; all of them were bilateral in distribution. Among other studied factors, only headset use (OR= 5.2, 95%CI = 1.7-16.1) and age (OR= 1.1, 95%CI = 1.0-1.2) were significant risk factors for developing SNHL among telephone operators. Conclusion: telephone operators are exposed to